JP4876820B2 - Coating method, coating apparatus, and display member manufacturing method - Google Patents

Description

  The present invention is used, for example, in the manufacturing field of color filters for color liquid crystal displays and array substrates, plasma display panels, optical filters, and the like. Specifically, a coating solution is discharged onto the surface of a coated member such as a glass substrate. However, the present invention relates to a coating method and a coating apparatus for forming a uniform coating film with a small defective film thickness region at the end, and an improvement in a manufacturing method and a manufacturing apparatus for a display member using them.

  A color liquid crystal display is composed of a color filter, a TFT array substrate, and the like. However, both the color filter and the TFT array substrate have a manufacturing process in which a low-viscosity liquid material is applied and dried to form a coating film. Many are included. For example, in a color filter manufacturing process, a black photoresist material coating film is formed on a glass substrate, and the coating film is processed into a lattice shape by a photolithographic method, and then red, blue, and green photoresist materials are formed between the lattices. These coating films are sequentially formed by the same method. In addition, after forming a coating film by applying a photoresist material, a manufacturing process for forming a column for obtaining a liquid crystal space injected between the color filter and the array substrate, There is also a manufacturing process for forming an overcoat coating film for smoothing unevenness.

  Conventionally, spinners, bar coaters, etc. have been used as coating devices for this coating film formation. However, the consumption of coating solution and power consumption are reduced, and the size of the device corresponding to a very large substrate of 2 m square or more is increased. In recent years, the use of slit coaters (for example, Patent Document 1) has increased. This known slit coater has a slit nozzle as a coating head, and a sheet-like coated member such as a glass substrate that travels in one direction while discharging a coating liquid from a slit-shaped discharge port provided in the slit nozzle. A coating film is formed on the substrate.

  In recent years, as the quality of products has improved, the accuracy of film thickness distribution required for slit coaters to be applied to substrates has been increasing. For example, film thickness unevenness of ± 3% or less excluding the edge of 10 mm It is hoped that. In general, a large film thickness variation is caused not at the center portion but at the end portion regardless of the coating direction or the substrate width direction which is the longitudinal direction of the slit nozzle. As for the width direction end, the film thickness distribution accuracy is determined by the performance of the slit nozzle and the characteristics of the coating liquid. On the other hand, regarding the end portion in the coating direction, the quality control of the coating start portion and the coating end portion greatly affects the formation of a film thickness distribution with small fluctuations. Especially when applying at high speed to improve productivity, unless the film thickness control at the start and end of application is optimized, the defective film thickness area at the end becomes longer and the product area with a constant film thickness becomes shorter. Thus, the effective utilization rate of the substrate decreases.

  With regard to the film thickness control means at the coating start part, many improvement means have been proposed due to the importance as described above, and a clearance between the substrate and the die is provided for discharging the coating liquid and slit nozzles for the substrate. (For example, Patent Document 2) in which the slit nozzle and the substrate are kept stationary, and the substrate is started to move after starting a certain time after the pump is driven to start discharging. (For example, Patent Document 3). However, in either case, in principle, the pump supply speed and the relative movement speed between the slit nozzle and the substrate are set to a predetermined value after the relative speed of movement between the slit nozzle and the substrate. It is not possible to control the film thickness to a predetermined value in the acceleration section (start-up section) until the relative movement speed between the substrates reaches a steady value. When coating at a high speed of 100 mm / s or more, the length that is passed by acceleration reaches several tens of millimeters in extreme cases. Therefore, in order to reduce this length to 10 mm or less, film thickness control means considering the acceleration section Is required. As such a film thickness control means, both the pump supply speed and the relative movement speed between the slit nozzle and the substrate are raised at a very low speed to obtain a constant film thickness, and then the pump supply speed and the relative movement between the slit nozzle and the substrate. An attempt is made to achieve a predetermined film thickness in the acceleration section by increasing the speed to a steady speed (for example, Patent Document 4), the pump supply speed and the rate of change of the relative movement speed between the slit nozzle and the substrate being the same. There is what has been tried (for example, Patent Document 5).

In addition, in a slit coater that coats a large substrate of 2m square or more, the device becomes large and heavy, and the inertia of the moving part increases, so the acceleration time until the relative moving speed between the slit nozzle and the substrate becomes a steady value, That is, the acceleration section becomes longer. If the acceleration interval becomes longer, the defective film thickness region also becomes longer. Therefore, in order to prevent this from happening, use a film thickness control means that takes into account the acceleration interval so that the film thickness becomes a predetermined value in the acceleration interval. This technology is essential even when the size is increased.
JP-A-6-339656 (5th column, 18th line to 9th column, 13th line, FIG. 1) JP 2002-113411 A (Column 5, line 30 to column 6, line 45, column 7, lines 3 to 31; FIGS. 1 and 5) JP-A-8-229482 (column 13, line 46 to column 15, line 48, FIG. 3) JP 2002-86044 A (column 9, line 43 to column 10, line 35, FIG. 5) JP-A-9-253563 (2nd column 42 line to 3rd column 5 line, 9th column 34th line to 10th column 49th line, FIGS. 2 and 6)

  However, the means of Patent Document 4 has a problem in that it takes extra tact time because it requires extra time to start up at an extremely low speed. On the other hand, in the means shown in Patent Document 5, since the pump supply speed is increased ahead of the relative movement speed between the slit nozzle and the substrate, the coating liquid is always excessively supplied. When there is a large amount of supply, there is a problem that a constant film thickness cannot be obtained in the acceleration section.

  The present invention has been made in order to solve the above-mentioned problems, and the object of the present invention is to provide a film thickness in the acceleration interval between the supply speed of the constant capacity pump and the relative movement speed between the slit nozzle and the substrate. Presenting means to be a predetermined value, minimize the defective film thickness section that does not reach the target film thickness range generated in the coating start part when the acceleration section of the moving part becomes long when applying at high speed or in a large apparatus, As a result, the uniform film thickness section can be maximized, and the effective product area on a single coated member can be maximized easily and without increasing the tact time, thereby improving productivity and yield. An object of the present invention is to provide a coating apparatus and method that greatly contributes to improvement, and a method for manufacturing a display member using this method.

The object of the present invention is achieved by the means described below.

Engaging Ru coated fabric method according to the present invention, it brought close to the coating member stationary with applicator having a discharge opening extending in one direction, and finally feed rate Qp of the coating liquid applicator from a constant displacement pump Supply the coating liquid from the applicator onto the member to be coated at a supply speed, and then supply the coating liquid from the constant capacity pump to the applicator at the steady supply speed Qs to apply the coating liquid from the applicator to the member to be coated. This is a coating method in which a coating film is formed on a member to be coated by performing a relative movement of the member to be coated with respect to the applicator at a steady moving speed Vs, and the relative movement is started ts seconds after the start of pre-dispensing. At the same time, the supply speed Qp of the constant displacement pump is started to increase to the steady supply speed Qs after tp seconds from the start of the relative movement, and the steady supply speed Qs after t seconds (t ≧ tp) from the start of the relative movement. Reach The ratio Q (t) / Qs between the supply speed Q (t) and the steady supply speed Qs up to and after the start of the relative movement t seconds (t ≧ tp) until the steady relative movement speed Vs is reached. The coating is characterized in that the speed V (t) and the ratio V (t) / Vs of the steady relative movement speed Vs are substantially the same.
The display member manufacturing method according to the present invention is characterized in that a display member is manufactured using the coating method described above.

Further, engagement Ru coating fabric device to the present invention, the applicator having a discharge opening extending in one direction to eject a coating liquid, a fixed displacement pump for supplying a coating liquid to the applicator, to be coating member In a coating apparatus for forming a coating film on a member to be coated, comprising: a holding table to be held; and a moving unit that relatively moves at least one of the applicator and the mounting table. At the start position, discharge of the coating liquid from the stationary applicator is started and pre-dispensing is finally performed at the supply speed Qp. The relative movement is started ts seconds after the start of the pre-dispensing, and tp from the start of the relative movement. After a second, the constant-rate pump supply speed Qp is started to increase to the steady supply speed Qs, and further, the supply speed Q (t ≧ t) after the start of relative movement until the steady supply speed Qs is reached. ) And the steady supply speed Qs, the ratio Q (t) / Qs, and the relative movement speed V (t) from the start of the relative movement to the steady relative movement speed Vs after t seconds (t ≧ tp) and the steady movement. It is characterized by having a control means for applying by making the ratio V (t) / Vs of the relative movement speed Vs substantially the same.

If the coating method and the coating apparatus according to the present invention are used, the ratio of the supply speed of the constant capacity pump and the relative movement speed between the slit nozzle / substrate to the respective steady speeds is increased and the pre-dispensing amount is further increased. The film thickness distribution can be fine-tuned by adjusting the speed increase timing, etc., so the film thickness can be set to a predetermined value from the acceleration section, and it can be applied at high speed or moved with a large device Even when the acceleration section of the part is long, the defective film thickness section that does not reach the target film thickness range that occurs at the coating start part is minimized, thereby making the uniform film thickness section the longest, on one coated member It can be easily realized to maximize the effective product area.
According to the method for manufacturing a display member according to the present invention, since the display member is manufactured using the above-described excellent coating method, an excellent coating quality display member having a long uniform film thickness section is high. It becomes possible to manufacture with high productivity and high yield.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
Figure 1 is a schematic front view of a slit coater 1 is a coating apparatus according to the present invention, FIG. 2, the first coating fabric methods that can be used as a guide of the present invention (hereinafter "application method 1) may represent a.) time diagram of a pumping speed and stage speed representing the FIG. 3, when representing a second coating fabric method according to the present invention (hereinafter "application method 2) is.) of the pumping rate and the stage speed representing the FIG. 4 is a time diagram of pump supply speed and stage speed representing a conventional coating method.

  Referring first to FIG. 1, a slit coater 1 of the present invention is shown. The slit coater 1 includes a base 2, and a pair of guide rails 4 are provided on the base 2. On the guide rail 4, a mounting table for the substrate A as a member to be coated, that is, a stage 6 is arranged. The stage 6 is driven by a linear motor (not shown) and reciprocates freely in the X direction indicated by an arrow in FIG. The moving speed of the stage 6 is referred to as a stage speed. The upper surface of the stage 6 is a vacuum suction surface made of suction holes, and can hold the substrate A by suction.

  Looking at the center of the base 2, there is a gate-shaped column 10. The support column 10 is provided with a vertical lift unit 70, and a slit nozzle 20 for applying the vertical lift unit 70 is attached.

  The slit nozzle 20 includes a front lip 22 and a rear lip 24 that extend in a direction perpendicular to the X direction (a direction perpendicular to the paper surface) and are overlapped in the X direction via a shim 32 and integrated with a plurality of connection bolts (not shown). Is bound to. A manifold 26 is formed at the center of the slit nozzle 20, and the manifold 26 also extends in the longitudinal direction of the slit nozzle 20 (direction perpendicular to the X direction). A slit 28 is formed below the manifold 26 so as to communicate therewith. The slit 28 also extends in the longitudinal direction of the slit nozzle 20, and the lower end thereof opens at the discharge port surface 36 that is the lowermost end surface of the slit nozzle 20 to form the discharge port 34. Since the slit 28 is formed by the shim 32, the slit gap (measured in the X direction) is equal to the thickness of the shim 32.

  The vertical lifting / lowering device unit 70 that lifts and lowers the slit nozzle 20 includes a suspension holding base 80 that holds the slit nozzle 20 in a suspended form, a lifting base 78 that lifts and lowers the suspension holding base 80, and a vertical guide for the lifting base 78. And a ball screw 76 for converting the rotational motion of the motor 72 into the linear motion of the lifting platform 78. The vertical lift unit 70 has a pair of left and right so as to support both ends of the slit nozzle 20 in the longitudinal direction, and each can be lifted and lowered independently, so that the inclination angle of the slit nozzle 20 in the longitudinal direction with respect to the horizontal can be arbitrarily set. . Thereby, the discharge port surface 36 of the slit nozzle 20 and the substrate A can be made substantially parallel over the longitudinal direction of the slit nozzle 20. Further, the vertical lift unit 70 can provide a clearance, that is, a clearance of any size between the substrate A on the stage 6 and the discharge port surface 36 of the slit nozzle 20.

  Further, when the right end portion of the base 2 is viewed in FIG. 1, the wiping unit 90 is mounted on the guide rail 4 so as to be movable in the X direction. In the wiping unit 90, a wiping head 92 having a shape that engages with the periphery of the discharge port 34 of the slit nozzle 20 is attached to the slider 96 via a bracket 94. The slider 96 is freely moved by the drive unit 98 in the longitudinal direction of the slit nozzle 20, that is, in a direction orthogonal to the X direction. The drive unit 98 and the tray 100 are fixed on the carriage 102. Since the carriage 102 is on the guide rail 4 and is guided by the guide rail 4 and can freely reciprocate in the X direction by a linear motor (not shown), the entire wiping unit 90 can reciprocate in the X direction. When wiping is performed, the entire wiping unit 90 is moved in the X direction to a position where the wiping head 92 is engaged with the slit nozzle 20, and the slit nozzle 20 is lowered and engaged with the wiping head 92. Then, when the driving unit 98 is driven to slide the wiping head 92 in the longitudinal direction of the slit nozzle 20, the coating liquid and other contaminants remaining in the vicinity of the discharge port 34 of the slit nozzle 20 are removed and cleaned. Can do. The removed coating liquid and the like are collected in the tray 100. The tray 100 is connected to a discharge line (not shown) and can discharge and collect a liquid such as a coating liquid accumulated inside. The tray 100 can also be used for collecting the coating liquid discharged from the slit nozzle 20 by air bleeding or the like. The wiping head 92 is preferably an elastic body such as rubber or a synthetic resin so that it can be engaged with the slit nozzle 20 evenly.

  Further, when viewing the left side of the base 2, a thickness sensor 120 for measuring the thickness of the substrate A is attached to the support base 122. The thickness sensor 120 preferably uses a laser. By measuring the thickness of the substrate A with the thickness sensor 120, the clearance that is the gap between the discharge port surface 36 of the slit nozzle 20 and the substrate A is always constant for any thickness of the substrate A. can do.

  Looking again at the slit nozzle 20, the upstream side of the manifold 26 of the slit nozzle 20 is always connected to a supply hose 60 connected to the coating liquid supply device 40 via an internal passage (not shown). A coating liquid can be supplied to the coating liquid 26 from the coating liquid supply apparatus 40. The coating liquid that has entered the manifold 26 is uniformly widened in the longitudinal direction of the slit nozzle 20 and is discharged from the discharge port 34 through the slit 28.

  The coating liquid supply device 40 includes a filter 46, a supply valve 42, a syringe pump 50, a suction valve 44, a suction hose 62, and a tank 64 on the upstream side of the supply hose 60. A coating liquid 66 is stored in the tank 64, and a back pressure of an arbitrary magnitude can be applied to the coating liquid 66 by being connected to a pressure air source 68. The coating liquid 66 in the tank 64 is supplied to the syringe pump 50 through the suction hose 62. In the syringe pump 50, a syringe 52 and a piston 54 are attached to the main body 56. Here, the piston 54 can reciprocate freely in the vertical direction by a drive source (not shown). The syringe pump 50 is a constant-capacity type pump that fills a syringe 52 having a constant inner diameter with a coating liquid, pushes it out by a piston 54, and supplies the slit nozzle 20 with a single substrate A. . When filling the syringe 52 with the coating liquid 66, the suction valve 44 is opened, the supply valve 42 is closed, and the piston 54 is moved downward. Further, when supplying the coating liquid filled in the syringe 52 toward the slit nozzle 20, the suction valve 44 is closed, the supply valve 42 is opened, and the piston 54 is moved upward, so that the piston 52 moves the syringe 52. Push up and discharge the coating solution inside. A product obtained by multiplying the moving speed of the piston 54 by the syringe cross-sectional area is a supply speed of the coating liquid, that is, a pump supply speed.

  Note that the linear motor, the motor 72, the coating liquid supply device 40, and the like that are operated by the control signal are all electrically connected to the control device 130. Then, a control command signal is transmitted to each device in accordance with an automatic operation program incorporated in the control device, and a predetermined operation is performed. When changing the conditions, if an appropriate change parameter is input to the operation panel 132, the change parameter is transmitted to the control device 130, and the change of the driving operation can be realized. In particular, in the coating liquid supply device 40, the syringe pump 50, the supply valve 42, the suction valve 44, and the switching valve 240 are electrically connected, and the control device 130 receives the electrical signal from the control device 130. Any operation can be performed according to the command. If the control device 130 is used, the operations of the coating liquid supply device 40, the up-and-down lift unit 70, and the stage 6 can be freely controlled, so that the pump supply speed and the relative movement speed between the slit nozzle 20 and the stage 6 or the substrate A are obtained. The stage speed and the drive start / stop timing of both can be arbitrarily set, and the coating film thickness distribution at the coating start portion and the coating end portion can be controlled arbitrarily.

Next, the 1st coating method used as the reference of this invention by the slit coater 1 is explained in full detail. First, when the origin of each operating part of the slit coater 1 is returned, each moving part moves to the standby position. That is, the stage 6 moves to the left end of FIG. 1 (position indicated by a broken line), the slit nozzle 20 moves to the uppermost position, and the wiping unit 90 moves so that the tray 100 comes to the lower position of the slit nozzle 20. Here, the coating liquid 66 is already filled from the tank 64 to the slit nozzle 20, and the operation of discharging the residual air inside the slit nozzle 20 has already been completed. At this time, the coating liquid supply device 40 is in a state where the syringe 52 is filled with the coating liquid 66, the suction valve 44 is closed, the supply valve 42 is opened, and the piston 54 is at the lowermost position. The nozzle 20 can be supplied.

  First, lift pins (not shown) are raised on the surface of the stage 6, and the substrate A is placed on the lift pins from a loader (not shown). Next, the lift pins are lowered to place the substrate A on the upper surface of the stage 6 and simultaneously hold it by suction. In parallel with this, the coating liquid supply device 40 is operated so that the vicinity of the discharge port 34 of the slit nozzle 20 is completely covered with the coating liquid, that is, in order to perform initialization, a predetermined amount of the coating liquid 66 is added. The liquid is supplied from the syringe pump 50 to the slit nozzle 20 and the coating liquid 66 is discharged from the slit nozzle 20 toward the tray 100. After the supply of the coating liquid 66 is stopped, the wiping unit 90 is moved so that the wiping head 92 is positioned just below the discharge port 34 of the slit nozzle 20. Then, after the slit nozzle 20 is lowered and the discharge port surface 36 of the slit nozzle 20 is engaged with the wiping head 92, the wiping head 92 is slid in the longitudinal direction of the slit nozzle 20 so that the vicinity of the discharge port 34 of the slit nozzle 20 is reached. Clean along the slit nozzle longitudinal direction. After the cleaning is completed, the wiping unit 90 returns to the original place (the right end in FIG. 1).

  When it is confirmed that the wiping unit 90 has moved to the right end of the base 2, the stage 6 on which the substrate A is placed starts to move. At this time, the slit nozzle 20 is in the wiping position far above the position where application is performed in the vertical direction, while the syringe pump 50 is stopped and stands by. Then, the substrate thickness is measured when the substrate A passes under the thickness sensor 120, and the stage 6 is stopped when the coating start portion of the substrate A reaches just below the discharge port 34 of the slit nozzle 20. At this time, by using the measured thickness data of the substrate A, the vertical lift unit 70 is driven so that the clearance between the discharge port surface 36 of the slit nozzle 20 and the substrate A, that is, the clearance becomes a predetermined value. Lower 20 to stop. In a state where the slit nozzle 20 and the stage 6 are completely stopped, as shown in FIG. 2, the syringe pump 50 is driven and pre-dispensed by a certain volume at the pump supply speed Qp. By this pre-dispensing, the coating liquid is filled in the gap between the stationary slit nozzle 20 and the substrate A, and a bead B is formed. 2 to 4 also show the relative positional relationship between the slit nozzle 20 and the substrate A at each timing and the coating state of the coating liquid 66 on the substrate A. After pre-dispensing, the syringe pump 50 and the stage 6 are started to operate simultaneously. At this time, the pump supply speed rises to the steady pump supply speed Qs, and the stage 6 rises to the steady stage speed Vs, but the pump supply speed Q and the stage speed V from the start of operation to the steady pump supply speed Qs and the steady stage speed Vs, respectively. In other words, the pump supply speed Q (t) and stage speed V (t) t seconds after the operation start (relative movement start) of the stage 6 is such that Q (t) / Qs is substantially the same as V (t) / Vs. Control to be The ratio of the pump supply speed Q (t) from the start of the pump operation to the steady pump supply speed Qs, Q (t) / Qs, is the ratio of the stage speed V from the start of the stage operation to the steady stage speed Vs V (t) / Vs. Is substantially the same as 1) the film thickness Th applied to the substrate A moving at the steady stage supply speed Qs at the steady pump supply speed Qs, and from the start of operation of the syringe pump 50 and the stage 6; It is applied in the acceleration section. 2) It means that both the pump supply speed Q (t) and the stage speed V (t) reach the steady pump supply speed Qs and the stage speed Vs in the same acceleration time ta required for the start-up. To do. This is because the necessary bead B is formed in advance by pre-dispensing, so if the pump supply speed Q (t) and the stage speed V (t) corresponding to the film thickness Th are set, the film thickness Th can be obtained in any case. It also shows that it can be applied. By controlling the pump supply speed Q of the syringe pump 50 and the application start part of the stage speed V of the stage 6, it is possible in principle to form the coating film C having the steady film thickness Th from the application start part. .

  Application is started as described above, and the coating liquid is supplied from the syringe pump 50 to the slit nozzle 20 at the steady pump supply speed Qs, and the stage 6 moves at the steady stage speed Vs, so that the substrate A has a thickness Th. The coating film C is stably formed. When the position slightly before the application end position of the substrate A comes directly below the discharge port 34 of the slit nozzle 20, the piston 54 is stopped to stop the supply of the application liquid 66, and then the application end position of the substrate A is the slit position. When it comes directly below the discharge port 34 of the nozzle 20, the vertical lift unit 70 is driven to raise the slit nozzle 20. As a result, the bead B formed between the substrate A and the slit nozzle 20 is cut off, and the application is completed.

  During this time, the stage 6 continues to operate, stops when it reaches the end point position, releases the suction of the substrate A, raises the lift pins, and lifts the substrate A. At this time, the lower surface of the substrate A is held by an unloader (not shown), and the substrate A is transported to the next step. When the substrate A is delivered to the unloader, the stage 6 lowers the lift pins and returns to the origin position. After returning to the origin position of the stage 6, the wiping unit 90 is moved so that the tray 100 is disposed below the discharge port 34 of the slit nozzle 20.

  After the movement is completed, the suction valve 44 is opened, the supply valve 42 is closed, the piston 54 is lowered, and the application liquid 66 is filled into the syringe 52. After the filling is completed, the piston 54 is stopped, the suction valve 44 is closed, the supply valve 42 is opened, the next substrate A is waited for, and the same operation is repeated.

In the above coating method, the control is performed so that the steady-state film thickness Th is obtained from the acceleration section of the syringe pump 50 and the stage 6 at the coating start portion, so that the defective film thickness that does not become the steady film thickness Th at the coating start portion. It is possible to minimize the section and maximize the product area of the steady film thickness Th. In particular, the acceleration time of the gantry that holds the stage and the slit nozzle with a slit coater for substrates of 2 m square or longer is increased during high-speed application of 100 mm / s or more, in which the actual length of the acceleration section becomes longer and the defective film thickness section becomes longer. when made, the method of coating this is quite useful, the defects thickness section can be easily to 10mm or less, the film thickness can be increased uniformly effective product area.

The second method of applying Ru engaged to the invention, except coating start is as follows is exactly the same as the first coating process. That is, after measuring the thickness of the substrate A, the vertical lift unit 70 is driven, and the slit nozzle 20 is lowered and stopped so that the clearance between the discharge nozzle surface 36 of the slit nozzle 20 and the substrate A becomes a predetermined value. Let With the slit nozzle 20 and the stage 6 completely stopped, as shown in FIG. 3, the syringe pump 50 is started to drive, and the coating liquid is discharged from the slit nozzle at the pump supply speed Qp, and is stationary. Pre-dispensing is performed so that the gap between the substrate 20 and the substrate A is filled with the coating liquid and the bead B is formed. Then, ts seconds after the operation of the syringe pump 50 starts, the operation of the stage 6 is started while the syringe pump 50 is supplying the coating liquid at the pump supply speed Qp. After this, the operation of the stage 6, that is, tp seconds after the start of relative movement between the slit nozzle 20 and the stage 6, and ts + tp seconds after the operation of the syringe pump 50 starts, the syringe pump 50 changes from the pump supply speed Qp to the steady pump supply speed. Start up to Qs. The pump supply speed Q (t) and the steady state in the acceleration section where the pump supply speed Qp rises to the steady pump supply speed Qs, that is, t seconds after the start of relative movement of the slit nozzle 20 and the stage 6 (where t ≧ tp). The ratio Q (t) / Qs of the pump supply speed Qs is set so that the stage speed V (t) and the steady stage speed Vs at t seconds after the start of relative movement of the slit nozzle 20 and the stage 6 (t ≧ tp) It is preferable to control the ratio V (t) / Vs to be substantially the same. That is, the stage speed V (t) reaches Vs × Qp / Qs at the timing when the syringe pump 50 starts to increase from the pump supply speed Qp. As a result, the coating is applied from the acceleration section at the film thickness Th applied to the substrate A moving at the steady stage speed Vs at the steady pump supply speed Qs. Note that the amount of pre-dispensing from the syringe pump 50 necessary for forming the bead B is adjusted by the amount of time ts from the start of pre-dispensing to the start of movement of the stage 6. By controlling the pump supply speed of the syringe pump 50 and the application start part of the stage speed of the stage 6, it is possible in principle to form the coating film C having the steady film thickness Th from the application start part. Even in the second coating method described above, as in the first coating method, the control is performed so that the film thickness Th at the steady state is reached from the syringe pump 50 of the coating start portion and the acceleration section of the stage 6. It is possible to minimize the defective film thickness section that does not become the steady film thickness Th at the coating start portion and maximize the product area of the steady film thickness Th. In particular, the coating method of the present invention demonstrates its power when applying at a high speed of 100 mm / s or more, or when using a large slit coater for substrates of 2 m square or more, where the passage length in the acceleration section becomes longer and the defective film thickness section becomes longer. The defective film thickness section can be easily reduced to 10 mm or less, and the product area can be enlarged. In particular, in the second coating method, since the operation of the syringe pump 50 is continuously started from pre-dispensing, the tact time is further shortened than in the first coating method, which is useful for improving productivity. Can do.

  In the above, at the timing when the syringe pump 50 starts to increase from the pump supply speed Qp, the stage speed V has reached Vs × Qp / Qs, and the acceleration section where the pump speed increases from the pump supply speed Qp to the steady pump supply speed Qs. The ratio Q / Qs between the pump supply speed Q and the steady pump supply speed Qs at the same time is controlled so as to be substantially the same as the ratio V / Vs between the stage speed V and the steady stage speed Vs in the same acceleration section. 3, the acceleration time for raising the pump supply speed of the syringe pump 50 from zero to the steady pump supply speed Qs is set to the same ta as the acceleration time for raising the stage speed of the stage 6 from zero to the steady stage speed Vs. That is. Using this relationship, the time tp from when the stage 6 starts to move until the syringe pump 50 starts to increase from the pump supply speed Qp is calculated as tp = ta × Qp / Qs, and is set to the eigenvalue. It may be determined.

  In addition, the ratio Qp / Qs of the pump supply speed Qp and the steady pump supply speed Qs during pre-dispensing when the coating method 2 is used is preferably 0.01 to 0.6, more preferably 0.05 to 0.3. To. When it is smaller than this range, it takes time for pre-dispensing and the overall tact time becomes longer, and when it is larger than this range, the pump supply is performed in the acceleration section where the pump supply speed Q and the stage speed V are being accelerated. The region where the ratio Q / Qs of the speed Q and the steady pump supply speed Qs is substantially the same as the ratio V / Vs of the stage speed V and the steady stage speed Vs (the pump supply speed Q is higher than the pump supply speed Qp during pre-dispensing) There is an inconvenience that the region (which becomes larger) becomes narrower and the defective film thickness region becomes longer.

  In the second coating method, the pre-dispensing is started at the pump supply speed Qp. However, the pump supply speed Qp may be reached by ts + tp seconds later. In this case, any speed profile may be used until the pump supply speed Qp is reached, for example, the pump supply speed Qp is increased in proportion to time or in proportion to the power of time, and once exceeds the pump supply speed Qp. A thing that shoots and reduces to the pump supply speed Qp can be applied. The pump supply speed Qp may be reached with any speed profile, but it is a necessary condition that a pre-dispensing amount for forming a bead B having a required size is provided in the gap between the slit nozzle 20 and the substrate A after ts seconds. .

The pump feed rate Q, acceleration time ta of stage moving speed V be any value, application method 1 as a reference of the present invention, are both effective application method 2 of the present invention. In particular, in a slit coater that can be applied to a glass substrate of 2 m square or more, the rising time ta, which is the acceleration time of the moving speed of the stage or slit nozzle, is 0.4 seconds or longer, which is longer than 0.2 seconds of a small apparatus. However, even in such a case, the coating method 1 and the coating method 2 of the present invention, which are references of the present invention, exert their effectiveness, and minimize the defective film thickness section that does not become the steady film thickness Th at the coating start portion. It is possible to maximize the product area of the steady film thickness Th. In addition, since neither the coating method 1 which is the reference of the present invention nor the coating method 2 of the present invention is operated to increase the tact time, the tact time is increased by carrying out the coating method of the present invention. Nor.

  A conventional application starting method is shown in FIG. Referring to FIG. 4, following the pre-dispensing at the pump supply speed Qp, the movement of the stage 6 is started after ts seconds from the start of the syringe pump driving, and the application is started. In the acceleration section in which startup is performed, the syringe pump increases from the pump supply speed Qp to the steady pump supply speed Qs during the time ta, and the stage 6 is increased from zero to the steady stage speed Vs. Therefore, the ratio (Q−Qp) / Qs of the difference (Q−Qp) between the pump supply speed Q in the acceleration section and the pump supply speed during pre-dispensing and the steady pump supply speed Qs (Q−Qp) / Qs is The stage speed Vs is controlled to be substantially the same as the ratio V / Vs. In this method, since the timing at which the speed increase starts from the pump supply speed Qp of the syringe pump 50 is matched with the operation start timing of the stage 6, the supply of the coating liquid from the syringe pump 50 is excessively preceded. Furthermore, it becomes thicker than the film thickness Th in the steady state, and does not contribute to the reduction of the defective film thickness section. Further, a coating film having a thickness Th is formed on the substrate A by supplying the coating liquid to the substrate A moving at the steady stage speed Vs at the steady pump supply speed Qs. If the stage speed V is determined by making Q / Qs and V / Vs substantially the same, the coating film C having a film thickness Th can be obtained in the acceleration section, but the pump supply speed Q and the stage speed V in the acceleration section are Since (Q-Qp) / Qs and V / Vs are determined to be substantially the same, the pump supply speed Q becomes higher with respect to the same stage speed V. From now on, the coating is thicker than the film thickness Th in the acceleration section. It can be seen that the film C is formed.

  In the above embodiment, the slit nozzle 20 is stationary and the stage 6 is moved to perform the application. However, even when the slit nozzle 20 is moved and the stage 6 is stationary, the application of the present invention is exactly the same. The effect is obtained. This is because the relative speed of the slit nozzle 20 and the substrate A on the stage 6 is the same, which means that either the slit nozzle 20 or the stage 6 moves. Accordingly, the stage speed V and the steady stage speed Vs may be referred to as the relative speed V and the steady relative movement speed Vs of the stage 6 with respect to the slit nozzle 20.

  Furthermore, the coating start method of the coating method 2 may be carried out after executing and ending a predetermined volume of pre-dispensing in the coating method 2 described above. In this case, pre-dispensing is performed in two steps.

  In addition, as a coating liquid which can apply this invention, a viscosity is 1-100 mPaS, More desirably, it is 1-50 mPaS, Although it is preferable from a coating property that it is Newtonian, it is applicable also to the coating liquid which has thixotropy. In particular, it is effective when a coating solution using a solvent having high volatility such as PGMEA, butyl acetate, ethyl lactate or the like is applied. Specific examples of the coating solution that can be applied include a resist solution, an overcoat material, a column forming material, and the like, in addition to the above-described black matrix for color filter and coating solution for forming RGB color pixels. As a member to be coated which is a substrate, a metal plate such as aluminum, a ceramic plate, a silicon wafer or the like may be used in addition to glass. Further, the coating state and coating speed to be used are 10 mm / s to 600 mm / s, more preferably 100 mm / s to 300 mm / s, the lip gap of the slit nozzle is 50 to 1000 μm, more preferably 80 to 200 μm, and the coating thickness is wet. It is 1-50 micrometers in a state, More preferably, it is 2-20 micrometers.

Hereinafter, the effect of the present invention will be described using examples.
Example 1
A non-alkali glass substrate having a thickness of 1100 × 960 mm and a thickness of 0.7 mm was washed and then applied using the slit coater 1. The slit nozzle had a discharge port length of 1100 mm and a slit gap of 100 μm, and a 1100 mm wide coating film could be formed on the substrate. The coating speed was 200 mm / s. The long side of 1100 mm was taken as the substrate width direction, and coating was performed in the short side direction of 960 mm. The coating solution was a red photosensitive negative resist for color filters, having a solid content concentration of 14% and a viscosity of 3 mPaS. The constant pump supply speed Qs from the syringe pump 50 at the time of application, that is, the thickness after vacuum drying was set to 4400 μl / s so that the thickness after vacuum drying was 2.8 μm, that is, Th = 20 μm immediately after application. Application is started by the second application method described above, the stage 6 is driven, and first, the substrate is moved so that the discharge port of the slit nozzle 20 is at the application start part of the substrate, that is, the position directly above the substrate edge. And stopped. Then, the slit nozzle was lowered so that the clearance between the substrate and the discharge nozzle surface of the slit nozzle was 100 μm. With the slit nozzle 20 and the substrate stopped, the syringe pump is driven as shown in FIG. 3 to perform pre-dispensing at a pump supply rate Qp = 325 μl / s, and after pre-dispensing is started, ts = 0. After 6 seconds, the stage 6 started moving. The stage 6 was raised to a steady stage speed Vs = 200 mm / s after ta = 0.4 seconds. Furthermore, after tp = 0.03 seconds from the start of the stage 6 movement, when the stage speed V of the stage 6 reaches 14.8 mm / s, a command is issued to the syringe pump 50 being driven at a pump supply speed of 325 μl / s. Then, start-up was started to bring the pump supply rate to the steady pump supply rate Qs = 4400 μl / s. Note that the steady pump supply speed Qs and the steady stage speed Vs are reached at the same timing, that is, the steady pump supply speed 0.37 seconds after the syringe pump 50 starts to increase from the pump supply speed Qp to the steady pump supply speed Qs. It was driven to reach Qs. By these driving, after t seconds from the start of movement of the stage 6 (where t ≧ tp = 0.03 seconds), the supply speed Q (t) of the syringe pump 50 is Q (t) = ((t−0. 03) /0.4) × Qs + Qp, and the stage speed V (t) is expressed as V (t) = (t / 0.4) × Vs. Here, from the above description, tp / ta × Qs = (0.03 / 0.4) × Qs = Qp, so that Q (t) / Qs = (t / 0.4) × Qs / Qs = t / 0.4, while the stage speed is V (t) / Vs = (t / 0.4) × Vs / Vs = t / 0.4. After t seconds (where t ≧ tp = 0.03 seconds), the ratio Q (t) / Qs between the supply speed Q (t) and the steady supply speed Qs until the steady supply speed Qs is reached, and the steady relative movement speed Vs. The ratio V (t) / Vs between the relative movement speed V (t) and the steady relative movement speed Vs until the value reaches is the same.
Then, as described above, the syringe pump 50 and the stage 6 are respectively driven to the steady pump supply speed Qs and the steady stage speed Vs for coating, and the discharge port of the slit nozzle 20 is positioned at the position of the glass substrate 955 mm from the substrate end. When 34 came, the syringe pump 50 was stopped, and the slit nozzle 20 was raised to finish the application when the glass substrate position of 960 mm from the substrate end was directly below the discharge port 34. After the above application, vacuum drying with an ultimate vacuum of 65 Pa was performed. The film thickness distribution in the coating direction was measured with a light interference type film thickness meter, and the film thickness distribution chart shown in FIG. 5 was obtained. From FIG. 5, the film thickness accuracy U at this time is calculated as U = (maximum value−minimum value) / (2 × average value) × 100 (%) in a region excluding the end 10 mm, and is 1.6%. In fact, less than 3% of the target was achieved.

Comparative Example 1
The method of patent document 3 is used for the application | coating start method, and the application | coating start starts the supply of a coating liquid to a slit nozzle by driving the syringe pump 50, without performing pre-dispensing from the state which the slit nozzle 20 and the board | substrate stopped. Starting up to a steady pump supply speed of 4400 μl / s in 0.2 seconds, 0.06 seconds after the start of driving of the syringe pump 50, the stage 6 is started to drive, and a steady stage speed of 200 mm / s is reached for 0.2 seconds. A glass substrate was coated and dried under exactly the same conditions as in Example 1 except that the process was started. Here, the supply speed Q (t) of the syringe pump 50 is Q (t) = (t / 0.2) × Qs, and the stage speed V (t) is V (t) = ((t−0.06). /0.2)×Vs. After t seconds from the start of driving the syringe pump 50 (where t ≧ 0.06 seconds), the ratio Q (t) / Qs = t between the supply speed Q (t) and the steady supply speed Qs until the steady supply speed Qs is reached. /0.2, the ratio of the relative movement speed V (t) until the steady relative movement speed Vs is reached and the steady relative movement speed Vs V (t) / Vs = (t−0.06) /0.2. (T) / Qs and V (t) / Vs are not the same. The film thickness distribution in the coating direction after drying was measured with a light interference type film thickness meter, and a film thickness distribution chart with a thick coating start portion shown in FIG. 6 was obtained. From FIG. 6, the film thickness accuracy U was calculated as U = (maximum value−minimum value) / (2 × average value) × 100 (%) in the region excluding the end 10 mm, and a value of 5.5% was obtained. Although the time from the start of driving the syringe pump 50 to the start of driving the stage 6 was adjusted, the film thickness accuracy was 5.5%, which was the best value, and the target of 3% could not be achieved.

Reference example 1
A color filter was manufactured using the slit coater 1. The slit nozzle had a discharge port length of 1100 mm and a slit gap of 100 μm, and a 1100 mm wide coating film could be formed on the substrate.

First, after washing an alkali-free glass substrate having a thickness of 1100 × 1300 mm and a thickness of 0.7 mm, the short side is the longitudinal direction of the slit nozzle, the black matrix coating liquid is 10 μm thick, and the clearance between the slit nozzle and the substrate is 100 μm. Application was at 150 mm / s. The first coating method that serves as a reference for the present invention was used for coating. That is, first, the stage 6 is driven to stop the substrate end, which is the application start position, immediately below the discharge port of the slit nozzle 20, and then the slit nozzle is lowered so that the clearance between the discharge port surface of the slit nozzle and the substrate is reduced. The slit nozzle was stopped at a position of 100 μm. The syringe pump was driven while the slit nozzle and the substrate were stationary, and 200 μl was pre-dispensed at a pump supply rate of 200 μl / s. After completion of pre-dispensing, the syringe pump and the stage 6 were started to be driven simultaneously, and 0.5 seconds later, the syringe pump was started up at a steady pump supply speed of 1650 μl / s, and the stage 6 was started up at a steady stage speed of 150 mm / s. The ratio Q (t) / Qs between the pump supply speed Q (t) and the steady pump supply speed Qs, and the ratio V (t) / Vs between the stage speed V (t) and the steady stage speed Vs in this acceleration section are the same. Since both the syringe pump 50 and the stage 6 are increased from zero to the steady pump supply speed Qs and the stage speed Vs over time, they are the same as t / 0.5. When the discharge port 34 of the slit nozzle 20 comes to a position 1295 mm from the substrate end, the syringe pump 50 is stopped, and the slit nozzle 20 is applied when the position 1300 mm from the substrate end is directly below the discharge port 34. The slit nozzle was lifted for completion. The black matrix coating solution applied at this time was a photosensitive one adjusted to a solid content concentration of 10% and a viscosity of 4 mPaS using titanium oxynitride as a light shielding material, acrylic resin as a binder, and PGMEA as a solvent. Using. The tact time for coating was 60 seconds. The coated substrate was vacuum dried to reach 65 Pa in 30 seconds for 60 seconds, and further dried on a 100 ° C. hot plate for 10 minutes. Next, after exposure, development, and peeling, heating was performed for 30 minutes on a 260 ° hot plate, curing was performed, and the pitch was 254 μm in the width direction of the substrate, the pitch was 85 μm in the longitudinal direction of the substrate, and the line width was 20 μm. A black matrix film having a lattice shape and a thickness of 1 μm was prepared. In addition, the coating thickness is measured in the state before the grid pattern is formed after drying, and the film thickness accuracy U is an area excluding the end 10 mm U = (maximum value−minimum value) / (2 × average value) × 100 ( %) Was 3% or less in both the substrate running direction and the width direction.

  Next, after wet cleaning, the coating solution for R color was applied at a thickness of 20 μm, a clearance between the slit nozzle and the substrate of 100 μm, and a coating speed of 150 mm / s. At this time, the pre-dispense is performed at a pump supply rate of 200 μl / s and a volume of 220 μl. After the pre-dispense is completed, the syringe pump and the stage 6 are started to be driven at the same time. The speed was 3300 μl / s, the stage 6 was raised to a steady stage speed of 150 mm / s, and the others were applied under exactly the same conditions as the black matrix solution. Since the syringe pump and the stage 6 start driving at the same time and reach their respective steady speeds in the same 0.5 seconds, the pump supply speed Q (t) The ratio Q (t) / Qs of the steady pump supply speed Qs and the ratio V (t) / Vs of the stage speed V (t) and the steady stage speed Vs were the same t / 0.5.

  The coating solution for R color was a photosensitive solution prepared by mixing an acrylic resin as a binder, PGMEA as a solvent, and Pigment Red 177 as a pigment, mixing them at a solid concentration of 10%, and adjusting the viscosity to 5 mPaS. The substrate coated with the 20 μm coating film was vacuum-dried to reach 65 Pa in 30 seconds for 60 seconds, and further dried for 10 minutes on a 100 ° C. hot plate. Next, exposure, development, and peeling were performed to leave an R-color coating film having a thickness of 2 μm only in the R pixel portion, and curing was performed by heating on a 260 ° C. hot plate for 30 minutes. Subsequently, a coating solution for G color was applied to a substrate on which a black matrix and an R color coating film were formed at a thickness of 20 μm, a clearance between the slit nozzle and the substrate of 100 μm, and an application speed of 150 mm / s. At this time, the pre-dispensing is performed at a pump supply rate of 200 μl / s and a volume of 210 μl. After the pre-dispensing is finished, the syringe pump and the stage 6 are started to be driven at the same time. The pump supply speed was 3300 μl / s, the stage 6 was raised from zero to a steady stage speed of 150 mm / s, and the others were applied under exactly the same conditions as the black matrix solution. Since the syringe pump and the stage 6 start driving at the same time and reach their respective steady speeds in the same 0.5 seconds, the pump supply speed Q (t) The ratio Q (t) / Qs of the steady pump supply speed Qs and the ratio V (t) / Vs of the stage speed V (t) and the steady stage speed Vs were the same t / 0.5. The substrate coated with the 20 μm coating film was vacuum-dried to reach 65 Pa in 30 seconds for 60 seconds, and further dried for 10 minutes on a 100 ° C. hot plate. Next, exposure, development, and peeling were performed to leave a G-color coating film having a thickness of 2 μm only on the G-color pixel portion, and curing was performed by heating on a 260 ° C. hot plate for 30 minutes. Further, a B-color coating solution was applied to a substrate on which a black matrix, R-color, and G-color coating films were formed at a thickness of 20 μm, a clearance between the slit nozzle and the substrate of 100 μm, and an application rate of 150 mm / s. At this time, the pre-dispense is performed at a pump supply rate of 200 μl / s and the volume is 200 μl. After the pre-dispense is completed, the syringe pump and the stage 6 are started to be driven at the same time. The pump supply speed was 3300 μl / s, the stage 6 was raised from zero to a steady stage speed of 150 mm / s, and the others were applied under exactly the same conditions as the black matrix solution. Since the syringe pump and the stage 6 start driving at the same time and reach their respective steady speeds in the same 0.5 seconds, the pump supply speed Q (t) The ratio Q (t) / Qs of the steady pump supply speed Qs and the ratio V (t) / Vs of the stage speed V (t) and the steady stage speed Vs were the same t / 0.5. The substrate coated with the 20 μm coating film was vacuum-dried to reach 65 Pa in 30 seconds for 60 seconds, and further dried for 10 minutes on a 100 ° C. hot plate. Next, exposure, development, and peeling were performed to leave a 2 μm-thick B-color coating film only on the B-color pixel portion, and curing was performed by heating on a 260 ° C. hot plate for 30 minutes. The G-color coating solution is an R-color coating solution and the pigment is Pigment Green 36 and the viscosity is adjusted to 5 mPaS with a solid content concentration of 10%. The B-color coating solution is an R-color coating solution. Pigment Blue 15 having a solid content concentration of 10% and a viscosity adjusted to 5 mPaS. The tact time when applying R, G, and B colors was 60 seconds. The coating quality is satisfactory for each color, and the film thickness distribution is also measured for each color after drying, and the film thickness accuracy U in the region excluding the end 10 mm is U = (maximum value−minimum value) / ( 2 × average value) × 100 (%), the substrate running direction and the width direction were good at 3% or less.

  Finally, ITO was deposited by sputtering. With this manufacturing method, 1000 color filters were produced. The obtained color filter had no coating unevenness in the product region excluding 10 mm from the edge of the substrate, the chromaticity was uniform, and the quality was satisfactory.

It is the schematic of the slit coater 1 which is a coating device which concerns on this invention. The first coating fabric methods that can be used as a guide of the present invention is a time diagram of the pumping speed and the stage speed representing the. It is a time diagram of the pumping speed and the stage speed representing the second coating fabric method according to the present invention. It is a time diagram of a pump supply speed and a stage speed representing a conventional coating method. 2 is a film thickness distribution diagram as a result of application in Example 1. FIG. It is a film thickness distribution diagram which is the result of applying in a comparative example.

Explanation of symbols

1 slit coater 2 base 4 guide rail 6 stage 10 portal gantry 20 slit nozzle (applicator)
22 Front lip 24 Rear lip 26 Manifold 28 Slit 32 Shim 34 Discharge port 36 Discharge port surface 38 Slope 40 Coating liquid supply device 42 Supply valve 44 Suction valve 46 Filter 50 Syringe pump 52 Syringe 54 Piston 56 Main body
60 Supply hose 62 Suction hose 64 Tank 66 Coating liquid 68 Air pressure source
70 Vertical Lifting Unit 72 Motor 74 Guide 76 Ball Screw 78 Lifting Base 80 Suspension Holding Base 90 Wiping Unit 92 Wiping Head 94 Bracket 96 Slider 98 Drive Unit 100 Tray 102 Carriage 120 Thickness Sensor 122 Supporting Base
130 Controller 132 Operation Panel A Substrate (Coating Member)
B Bead C Coating film Q Pump supply speed Qs Steady pump supply speed Th: Film thickness V Stage speed Vs Steady stage speed ta Acceleration time tp Time from start of stage drive to start of syringe pump acceleration ts From start of syringe pump drive Time to start driving the stage

Claims (3)

An applicator having a discharge port extending in one direction is brought close to a stationary member to be coated, and a coating liquid is finally supplied from the constant-capacity pump to the coating device at a supply speed corresponding to the supply speed Qp. The coating liquid is pre-dispensed from the applicator, and then the coating liquid is supplied from the constant capacity pump to the applicator at a steady supply speed Qs, and the coating liquid is discharged from the applicator to the coated member. Is a coating method for forming a coating film on a member to be coated at a steady movement speed Vs, starting relative movement ts seconds after the start of pre-dispensing, and tp seconds after the start of relative movement. Starts to increase the supply speed Qp of the constant displacement pump to the steady supply speed Qs, and further, the supply speed Q (t) until the steady supply speed Qs is reached t seconds (t ≧ tp) after the start of relative movement. The ratio Q (t) / Qs of the steady supply speed Qs, the relative movement speed V (t) after reaching the steady relative movement speed Vs after t seconds (t ≧ tp) from the start of the relative movement, and the steady relative movement A coating method, wherein the coating is performed with the ratio V (t) / Vs of the speed Vs being substantially the same. 2. A display member manufacturing method, wherein the display member is manufactured using the coating method according to claim 1 . An applicator having a discharge port extending in one direction for discharging the coating liquid, a constant capacity pump for supplying the coating liquid to the applicator, a mounting table for holding a member to be coated, and the applicator and the mounting table In a coating apparatus that includes a moving means for relatively moving at least one of the coating members and forms a coating film on the member to be coated, the coating liquid is also applied from the stationary applicator at the coating start position on the stationary member to be coated. The pre-dispensing is started to finally supply the supply speed Qp, the relative movement is started ts seconds after the start of the pre-dispensing, and the supply speed Qp of the constant capacity pump is steady after tp seconds from the start of the relative movement. The supply speed Qs is started to increase, and the ratio Q (t) between the supply speed Q (t) and the steady supply speed Qs until t reaches the steady supply speed Qs after t seconds (t ≧ tp) from the start of relative movement. ) / Qs and the ratio of the relative movement speed V (t) to the steady relative movement speed Vs after t seconds (t ≧ tp) from the start of the relative movement and reaching the steady relative movement speed Vs V (t) / An applicator comprising control means for applying Vs substantially identically.

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